Manual pool vacuums are known in the art. These apparatus typically include an operational head having a substantially planar bottom. Wheels on opposing sides of the head are installed to preserve the planar bottom just over the pool's surface. A hose typically installed centrally on the head connects to a pool filtration system. The pump of the filtration system draws water and debris toward the vacuum, under the vacuum head, through the hose and into the filter where debris is trapped. Since the bottom of the head is in close proximity to the pool surface, a Venturi effect is created, increasing suction at the vacuum head and making it more difficult to move along the pool's surface.
To operate the vacuum, the head is moved along the pool's surface using a long extendable pole connected to the vacuum head. The wheels are normally oriented on the head for back-and-forth motion. This is because users can exert back-and-forth pressure on the pole more easily than other directions. Although the customary back-and-forth motion is more efficient than other directions due to posture and the user's orientation to the vacuum head, users occasionally desire to sweep the vacuum head side-to-side in the event a portion of the pool's surface or errant debris is missed during a first pass. This side-to-side action, already difficult due to viscosity and suction, is made even more difficult because the wheels travel only in two directions.
Omni-directional wheels are also known in the art. Omni-directional wheels have small rollers around their circumference which are perpendicular to the axis of rotation, allowing them to be driven forward, backward, and side-to-side. State of the art omni-directional wheels are typically expensive to produce, having multiple different moving parts, and difficult to assemble, requiring fasteners or other mechanisms to hold them together. For these reasons they are disfavored for use in pool vacuums and other applications where cost and ease of use are at a premium.
It is therefore an object of the invention is to provide an omni-directional wheel for a pool vacuum head that rolls from side-to-side and diagonally in addition to back and forth. Another object of the invention is to provide an omni-directional wheel for a pool vacuum head that is simple and inexpensive to mold, and easy to assemble and install. Another object of the invention is to provide an omni-directional wheel that can be readily used on an existing pool vacuum head without changing the head's basic structure or theory of operation. These and other objects are more fully discussed in the following summary, description and claims.